SAPEM Chapter 1 2nd Edition 2014

SOUTH AFRICAN

PAVEMENT ENGINEERING MANUAL

Chapter 1

Introduction

AN INITIATIVE OF THE SOUTH

AFRICAN NATIONAL ROADS AGENCY SOC LTD

Date of Issue: October 2014

Second Edition

South African Pavement Engineering Manual Chapter 1: Introduction 2013 South African National Roads Agency SOC Ltd. All rights reserved. First edition published 2013 Second edition published 2014 Printed in the Republic of South Africa SET: ISBN 978-1-920611-00-2 CHAPTER: ISBN 978-1-920611-01-9

www.nra.co.za [email protected]

SOUTH AFRICAN

PAVEMENT ENGINEERING MANUAL

Chapter 1

Introduction

AN INITIATIVE OF THE SOUTH AFRICAN NATIONAL ROADS AGENCY SOC LTD

Date of Issue: October 2014

Second Edition

FOREWORD

The South African Pavement Engineering Manual (SAPEM) is the culmination of many hours of work by dedicated and passionate road industry professionals. SANRAL will always remain indebted to those who so generously gave of their time. The spirit and generosity of South Africas road industry is reflected in the manual. This manual captures the knowledge and expertise of each task group ably led and supported by many contributors, who were driven by their sheer passion for the industry and willingness to share their experience with all of us. It is worth noting the evolution of this manual, which started off as a materials manual for SANRAL. As time proceeded, the value of the materials manual was recognized by the other road authorities (Provincial and Metropolitan) who supported the idea of a unified guideline taking into account the different needs of the authorities for the design of road pavements. Infrastructure for the transportation of goods and people is crucial for generating economic growth, alleviating poverty and increasing South Africas global competiveness. Roads play a critical role being the arteries of the economy in the socio-economic development of South Africa. And, as one of the largest capital spending agencies in Government in this sector, we are duty bound to maximize value for money for those whom we serve, and to reduce overall spending through efficient design and construction of pavements in these challenging economic times,

without compromising the standards, quality and excellent service we deliver to motorists. The manual comprises fourteen chapters covering a range of elements of pavement engineering. The chapters, inter alia, include the history of roads, the development of pavement engineering with time through the understanding of the behaviour of materials and their utilization, the influence of the environment and traffic, the interface between tyre and pavement, references to testing methods guiding the reader through the numerous tests to be conducted, and laboratory management. It explains relevant concepts, tells the reader of the dos and donts, and also contains guidelines on the investigation of the road prism, the pavement and geology, and suggests the expertise required for carrying out geotechnical investigations. This is a comprehensive guideline manual, not a policy manual. It is to be regarded as a best practice guideline, providing the sequence of steps for practitioners. Its benefits will manifest over time with its use, with the harmonization of designs and standards. It predominantly provides advice and guidance for the design of safe, state of the art, cost effective taking into account the carbon footprint pavements for motorists, thus reducing the cost of transport. SAPEM is a guide to all users students, academics and practitioners and is not a replacement for the principles of pavement engineering design and good engineering judgement. We trust that this manual will assist in the education and development of future pavement engineers, and continue to promote cost effective designs of road pavements. It is a living document, and will be periodically updated to make provision for newly adopted technologies. I would like to acknowledge the contribution of the many individuals who, over the years, have knowingly, or otherwise, contributed to the development of this manual. Thank you all.

Nazir Alli CEO The South African National Roads Agency SOC Limited

1. Introduction

2. Pavement Composition and Behaviour

3. Materials Testing

4. Standards

5. Laboratory Management

6. Road Prism and Pavement Investigations

7. Geotechnical Investigations and Design Considerations

8. Material Sources

9. Materials Utilisation and Design

10. Pavement Design

11. Documentation and Tendering

12. Construction Equipment and Method Guidelines

13. Acceptance Control

14. Post-Construction

BACKGROUND

TESTING AND LABORATORY

INVESTIGATION

DESIGN

DOCUMENTATION AND TENDERING

IMPLEMENTATION

QUALITY MANAGEMENT

POST CONSTRUCTION

You are here

South African Pavement Engineering Manual

Chapter 1: Introduction

Preliminary Sections

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SCOPE

The South African Pavement Engineering Manual (SAPEM) is a reference manual for all aspects of pavement engineering. SAPEM is a best practice guide. There are many relevant manuals and guidelines available for pavement engineering, which SAPEM does not replace. Rather, SAPEM provides details on these references, and where necessary, provides guidelines on their appropriate use. Where a topic is adequately covered in another guideline, the reference is provided. SAPEM strives to provide explanations of the basic concepts and terminology used in pavement engineering, and provides background information to the concepts and theories commonly used. SAPEM is appropriate for use at National, Provincial and Municipal level, as well as in the Metros. SAPEM is a valuable education and training tool, and is recommended reading for all entry level engineers, technologists and technicians involved in the pavement engineering industry. SAPEM is also useful for practising engineers who would like to access the latest appropriate reference guideline. SAPEM consists of 14 chapters covering all aspects of pavement engineering. A brief description of each chapter is given below to provide the context for this chapter, Chapter 1. Chapter 1: Introduction discusses the purpose, scope, contents and application of this SAPEM manual. A history of roads, the basic principles of roads and the purpose and classification of roads are discussed. In addition, for pavement engineering projects, the institutional responsibilities; statutory requirements in terms of environmental, mineral exploitation, and health and safety; and planning and time scheduling are given. The life cycle of road design is also discussed. A glossary of terms and abbreviations used in all the SAPEM chapters is included in Appendix A. A list of the major references and guidelines for pavement engineering is given in Appendix B. Chapter 2: Pavement Composition and Behaviour includes typical pavement structures, material characteristics and pavement types, including both flexible and rigid pavements, and surfacings. Typical materials and pavement behaviour are explained. The development of pavement distress, and the functional performance of pavements are discussed. As an introduction, and background for reference with other chapters, the basic principles of mechanics of materials and material science are outlined. Chapter 3: Materials Testing presents the tests used for all material types used in pavement structures. The tests are briefly described, and reference is made to the test number and where to obtain the full test method. Where possible and applicable, interesting observations or experiences with the tests are mentioned. Chapters 3 and 4 are complementary. Chapter 4: Standards follows the same format as Chapter 3, but discusses the standards used for the various tests. This includes applicable limits (minimum and maximum values) for test results. Material classification systems are given, as are guidelines on mix and materials composition. Chapter 5: Laboratory Management covers laboratory quality management, testing personnel, test methods, and the testing environment and equipment. Quality assurance issues, and health, safety and the environment are also discussed. Chapter 6: Road Prism and Pavement Investigation discusses all aspects of the road prism and pavement investigations, including legal and environmental requirements, materials testing, and reporting on the investigations. The road pavement investigations include discussions on the investigation stages, and field testing and sampling (both intrusively and non-intrusively), and the interpretation of the pavement investigations. Chapters 6 and 7 are complementary. Chapter 7: Geotechnical Investigations and Design Considerations covers the investigations into fills, cuts,

structures and tunnels, and includes discussion on geophysical methods, drilling and probing, and stability assessments. Guidelines for the reporting of the investigations are provided. Chapter 8: Material Sources provides information for sourcing materials from project quarries and borrow pits, commercial materials sources and alternative sources. The legal and environmental requirements for sourcing materials are given. Alternative sources of potential pavement materials are discussed, including recycled pavement materials, construction and demolition waste, slag, fly ash and mine waste. Chapter 9: Materials Utilisation and Design discusses materials in the roadbed, earthworks (including cuts and fills) and all the pavement layers, including soils and gravels, crushed stones, cementitious materials, primes, stone precoating fluids and tack coats, bituminous binders, bitumen stabilized materials, asphalt, spray seals and micro surfacings, concrete, proprietary and certified products and block paving. The mix designs of all materials are discussed.




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Chapter 10: Pavement Design presents the philosophy of pavement design, methods of estimating design traffic and the pavement design process. Methods of structural capacity estimation for flexible, rigid and concrete block pavements are discussed. Chapter 11: Documentation and Tendering covers the different forms of contracts typical for road pavement projects; the design, contract and tender documentation; the tender process; and the contract documentation from the tender award to the close-out of the Works. Chapter 12: Construction Equipment and Method Guidelines presents the nature and requirements of construction equipment and different methods of construction. The construction of trial sections is also discussed. Chapters 12 and 13 are complementary, with Chapter 12 covering the proactive components of road construction, i.e., the method of construction. Chapter 13 covers the reactive components, i.e., checking the construction is done correctly. Chapter 13: Quality Management includes acceptance control processes, and quality plans. All the pavement layers and the road prism are discussed. The documentation involved in quality management is also discussed, and where applicable, provided.

Chapter 14: Post-Construction incorporates the monitoring of pavements during the service life, the causes and mechanisms of distress, and the concepts of maintenance, rehabilitation and reconstruction.

FEEDBACK

SAPEM is a living document. The first edition was made available in electronic format in January 2013, and a second edition in October 2014. Feedback from all interested parties in industry is appreciated, as this will keep

SAPEM relevant. To provide feedback on SAPEM, please email [email protected].




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ACKNOWLEDGEMENTS

This compilation of this manual was funded by the South African National Road Agency SOC Limited (SANRAL). The project was coordinated on behalf of SANRAL by Kobus van der Walt and Steph Bredenhann. Professor Kim Jenkins, the SANRAL Chair in Pavement Engineering at Stellenbosch University, was the project manager. The Cement and Concrete Institute (C & CI) and Rubicon Solutions provided administrative support. The following people contributed to the compilation of Chapter 1:

Task Group Leader: Professor Kim Jenkins, Stellenbosch University Jayshree Govender, SANRAL Pierre Roux, SANRAL Arthur Taute, SMEC South Africa Kobus van der Walt, SANRAL This SAPEM manual was edited by Dr Fenella Johns, Rubicon Solutions. Photos for this chapter were provided by:

Dr Lucas-Jan Ebels, UWP Consulting Professor Kim Jenkins, Stellenbosch University Arthur Taute, SMEC South Africa




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TABLE OF CONTENTS

1. Background ......................................................................................................................................... 1

1.1 Purpose of SAPEM ........................................................................................................................ 1 1.1 Scope and Style of SAPEM ............................................................................................................ 1 1.2 Contents and Structure of SAPEM .................................................................................................. 2 1.3 How to Use SAPEM ...................................................................................................................... 3

2. History of Roads ................................................................................................................................. 4 2.1 Development of Roads ................................................................................................................. 4 2.2 History of Pavement Design .......................................................................................................... 6

2.2.1. AASHO Road Test ............................................................................................................ 7 2.3 Necessity of Roads ....................................................................................................................... 8

3. Basic Principles of Roads ................................................................................................................. 10

3.1 Political Pyramid ........................................................................................................................ 10 3.2 Technical Pyramid ...................................................................................................................... 10

4. Purpose and Classification of Roads ................................................................................................ 12 5. Institutional Responsibilities ........................................................................................................... 14

5.1 Owners ..................................................................................................................................... 14 5.2 Administrators ........................................................................................................................... 14 5.3 Designers .................................................................................................................................. 14 5.4 Construction .............................................................................................................................. 14

6. Statutory Requirements ................................................................................................................... 15

6.1 Environmental Requirements ...................................................................................................... 15 6.2 Mineral Exploitation .................................................................................................................... 16

6.2.1. Definitions .................................................................................................................... 16 6.2.2. Background ................................................................................................................... 16 6.2.3. Regulatory Overview ...................................................................................................... 16

6.3 Health and Safety Legislation ...................................................................................................... 17

7. Road Design Life Cycle ..................................................................................................................... 19

8. Planning and Time Scheduling ......................................................................................................... 23

8.1 Non-Technical Factors ................................................................................................................ 23 8.1.1. Land Acquisition ............................................................................................................ 23 8.1.2. Climate Restrictions ....................................................................................................... 24 8.1.3. Survey Considerations .................................................................................................... 24 8.1.4. Budget ......................................................................................................................... 24 8.1.5. Environmental Approvals ................................................................................................ 25

8.2 Typical Time Scheduling Requirements for Road Projects .............................................................. 25 8.2.1. Preliminary Investigation and/or Route Location ............................................................... 25 8.2.2. Preliminary Design Phase ............................................................................................... 25 8.2.3. Detailed Design ............................................................................................................. 25 8.2.4. Tender Documentation ................................................................................................... 25 8.2.5. Construction and Defects Notification Period .................................................................... 25

References and Bibliography ..................................................................................................................... 27

Appendix A: Glossary and Abbreviations

Appendix B: Major Guidelines and Manuals




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LIST OF TABLES

Table 1. Road Classification Systems ........................................................................................................ 13 Table 2. Key Environmental Requirements for the Mineral and Petroleum Resources Development Act ........... 17 Table 3. Phases of Road Design ............................................................................................................... 20 Table 4. Types of Land ............................................................................................................................ 24

LIST OF FIGURES

Figure 1. Typical Roman Pavement.............................................................................................................. 4 Figure 2. Pavement Structure ..................................................................................................................... 5 Figure 3. Bains Kloof Pass .......................................................................................................................... 6 Figure 4. Conceptual Impact of Technological Developments on Roads ........................................................... 6 Figure 5. Impassable Unsurfaced Roads Due to Wet Conditions, Early 20th Century ......................................... 7 Figure 6. AASHO Road Test ........................................................................................................................ 8 Figure 7. Road Concepts Political and Technical Pyramids for Roads ............................................................. 10 Figure 8. Functional Classification of Roads in South Africa .......................................................................... 12 Figure 9. Pavement Engineering Cycle of Technology .................................................................................. 19 Figure 10. Construction and Defects Notifications ......................................................................................... 26



Section 1. Background

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1. BACKGROUND

1.1 Purpose of SAPEM

The purpose of the South African Pavement Engineering Manual (SAPEM) is to provide a Best Practice Guideline for pavement engineering in the South African roads industry. This includes application at National, Provincial and Tertiary levels of Government. The need for such a manual arises for a number of reasons:

Guiding inexperienced engineers: New entrants into pavement engineering, of all ages, need a roadmap, or an overview of different areas of pavement technology and best practice, steps to follow, and the dos and donts as developed by the road authorities over time.

Capturing experience: The skewed distribution of ages in the industry is resulting in the baby-boomers going into retirement. The loss of their knowledge and expertise will be detrimental to the roads industry and therefore needs to be captured, where possible.

Referencing: Many manuals and technical, best practice guidelines are in existence, but some have become redundant or been superseded. SAPEM aims to provide an overview and reference of all of the pertinent

standards and guidelines. References for all relevant guidelines are provided, including, where possible, links to where the documents are available for download.

Education and training: Educational institutions require applicable reference material for their educational courses in pavement engineering. SAPEM fulfils this need.

Road Authority needs: Significant overlap exists between the pavement technologies used by the three tiers of government. Many road authorities do not have the capacity to develop their own, or to update, outdated materials manuals. SAPEM fulfils this role by providing for the needs of all road authorities. The divergent areas, e.g., low volume roads versus heavily trafficked roads, are addressed through caveats, which make provision for the different requirements and methods used in Metro, Municipal, Provincial and National Road Authorities.

Future revisions: Technology used in pavement engineering is constantly developing and advancing. Through web-based downloads, SAPEMs chapters can be effectively updated and accessed. This system supports the living nature of the document.

SAPEM covers all aspects of roads, including fills, cuts, tunnels and foundations.

1.1 Scope and Style of SAPEM

The scope of SAPEM extends beyond that of merely a materials manual. SAPEM provides an overarching perspective of all aspects of pavement engineering, incorporating associated specialities such as geotechnical investigations and tunnelling, material behaviour and selection, and pavement design principles. SAPEM places each of these activities in perspective giving insight into their function and provides the applicable guiding documents, but does not provide unnecessary detail that can be found in the best practice references. The only areas of detail in SAPEM are the undocumented technologies, for which accepted and up to date guideline documents are not available. This document refers only to accepted practice. Where possible, insights into the application of principles and topics in other guidelines are provided. The entire road prism is covered in SAPEM, incorporating embankments and cuttings and their investigation, as well as the investigation of bridge foundations. The main focus is on the pavement structure, i.e., subgrade, selected subgrade, subbase, base and surfacing layers. However, because guideline documentation for the rest of the road prism is not well defined elsewhere, it is incorporated into SAPEM. SAPEM is a guideline and not a policy manual there is a difference:

Policy manuals are structured to encourage practitioners to strictly follow the process. This results in going through the motions without the need for a critical analysis for why each step is taken and whether other steps are necessary.

Guidelines aim to strike a balance between prescription and freedom of interpretation. Sufficient information is provided for a practitioner to make interpretations and where necessary, to adapt methodologies and approaches for a given set of circumstances. SAPEM provides a sequence of processes for practitioners with a logical approach to pavement engineering practice to be carried out for a road authority, starting with applicable documents/contracts, through investigation and testing, culminating in the appropriate materials design and documentation.

Role of SAPEM

SAPEM aims to be the first stop for all issues relating to pavement engineering. It is not an all encompassing reference, but provides links to other useful and necessary references, guidelines and manuals.




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1.2 Contents and Structure of SAPEM

SAPEM is structured in several modules with each incorporating several chapters:

Background: The background module includes discussion on the scope and structure of technical, environmental and legal issues. Chapter 1: Introduction discusses the application of this

SAPEM manual, and the institutional responsibilities, statutory requirements, basic principles of roads, the road design life cycle, and planning and time scheduling for pavement engineering projects. A glossary of terms and abbreviations used in all the SAPEM chapters is included in Appendix A. A list of the major references and guidelines for pavement engineering is given in Appendix B.

Chapter 2: Pavement Composition and Behaviour includes typical pavement structures, material characteristics and pavement types, including both flexible and rigid pavements, and surfacings. Typical materials and pavement behaviour are explained. The development of pavement distress, and the functional performance of pavements are discussed. As an introduction, and background for reference with other

chapters, the basic principles of mechanics of materials and material science are outlined.

Laboratory and Testing: This module has three chapters, and includes all topics related to laboratories and materials testing. Chapter 3: Materials Testing presents the tests used for all material types in pavement structures. The

tests are briefly described, and reference is made to the test number and where to obtain the full test method. Where possible and applicable, interesting observations or experiences with the tests are mentioned.

Chapter 4: Standards follows the same format as Chapter 3, but discusses the standards used for the various tests. This includes applicable limits (minimum and maximum values) for test results, and gives material classification systems, and guidelines on mix and materials composition.

Chapter 5: Laboratory Management covers laboratory quality management, testing personnel, test methods, and the testing environment and equipment. Quality assurance issues, and health, safety and the environment are also discussed.

Investigation: The investigation module covers the investigations pertaining to the road prism, pavement, geotechnical aspects, as well as material sources. Chapter 6: Road Prism and Pavement Investigation discusses all aspects of the road prism and road

pavement investigations, including legal and environmental requirements, materials testing, and reporting on the investigations.

Chapter 7: Geotechnical Investigations and Design Considerations covers the investigations into potential problem subgrades, fills, cuts, structures and tunnels. Guidelines for the reporting of the investigations are provided.

Chapter 8: Material Sources provides information for sourcing materials from project quarries and borrow pits, commercial materials sources and alternative sources.

Design: The design module deals with material utilisation, mix designs and structural designs, and the analysis of traffic. Chapter 9: Materials Utilisation and Design discusses materials in the roadbed, earthworks and all the

pavement layers. The mix designs of all materials are included. Chapter 10: Pavement Design presents the philosophy of pavement design, methods of estimating design

traffic and the pavement investigation process. Methods of structural capacity estimation for flexible, rigid and concrete block pavements are discussed.

Documentation and Tendering Chapter 11: Documentation and Tendering covers the different forms of contract typical for road

pavement projects, the design, contract and tender documentation, and the tender process.

Implementation Chapter 12: Construction Equipment and Method Guidelines presents the nature and requirements of

construction equipment and different methods of construction. The construction of trial sections is also discussed.

Quality Management Chapter 13: Quality Management includes acceptance control processes and quality plans. All the

pavement layers and the road prism are discussed. The documentation involved in quality management is also discussed, and where applicable, provided.

Post-Construction Chapter 14: Post-Construction incorporates the monitoring of pavements during the service life, the

causes and mechanisms of distress, and the concepts of maintenance, rehabilitation and reconstruction.

SAPEM is a Guideline

SAPEM is best practice guideline. It is not a specification and does not have legal standing in a court of law.




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1.3 How to Use SAPEM

SAPEM has been created by practitioners for practitioners, representing all sectors of the roads industry, including road authorities, consultants, contractors, suppliers, researchers and machine manufacturers. You should follow the tips provide in the green and red boxes when using SAPEM.

Using SAPEM: Do

Do use SAPEM as a roadmap to guide you through a particular process in road

engineering to help you access the most relevant and up-to-date approaches, methods and techniques.

Do use the references provided to gain more detailed knowledge on a specific area. This will not only supplement your knowledge, but can also provide the necessary specification guidelines, test methods and available standard documentation.

Do be aware of differences between the requirements of road authorities. SAPEM has been drawn up generically for the highest level of application of pavement technology. However, where possible, caveats for provincial, municipal, district and metro roads are provided.

Using SAPEM: Dont

Dont consider SAPEM as an exhaustive compilation of all the details that you may

require. SAPEM only provides an overview, and includes many references to the latest detailed approaches, and procedures to cover the rest. Use the references.

Dont follow SAPEM by rote without critical consideration and decision making for your particular roads needs.

Dont ignore basic engineering judgement. SAPEM can only supplement knowledge and cannot replace judgement.

Dont consider SAPEM to replace mentors. Use it as a supplementary source of guidance and reference.

Dont use SAPEM as the main source of information for affiliated fields that have some

relation to pavements, e.g., geotechnical investigations and tunnelling. SAPEM aims to include some information on these areas for completeness, but is by no means a definitive source of guidance in specialist areas.



Section 2: History of Roads

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2. HISTORY OF ROADS

This section looks at the history of roads, from their development, to the history of pavement design. The necessity of roads is also discussed.

2.1 Development of Roads

An understanding of how pavement technology evolved requires a look back into the historical developments of roads. In ancient times there was nothing more than a sparse network of tracks for humans to reach feeding and drinking places. These tracks differed only slightly from the tracks made by the movement of foraging animals. The primary difference was that obstacles, e.g., boulders, were removed from the more important routes and thorn bushes were trimmed back by humans. More elaborate lines of communication than these simple tracks did not appear until the number of humans in certain areas reached a stage where their social structures and networks demanded more permanent contact between communities. Roads thus appeared when groups of people started to interact with each other by travelling, doing business,

fighting, and socializing. This occurred around 3500 BC. At this time, the invention of the wheel and development of chariots and wagons showed that the existing soil or subgrade on the interlinking routes was inadequate. Layers of better quality material were required to protect the subgrade, giving rise to the pavement structure. The earliest records of paved roads for wheeled traffic date from about 2200 BC in Babylonia (modern Iraq), in Crete from about 1500 BC and in Egypt from about 540 BC. In Europe, the first substantial roads were built by the Romans, with a network of more than 100 000 kilometres of road built between 400 BC and 400 AD. The Roman roads were cambered to shed rainwater and were constructed on a foundation of large stones with a wearing course of smaller stones and gravel, constrained between raised stone kerbs, as illustrated in Figure 1 from McCauley, 1974).

Figure 1. Typical Roman Pavement

The Romans were the best road builders of the remote ages. Conquests achieved through war games were one of the reasons for this. The Romans needed a good network of roads to control their conquered subject-nations. The army needed to be able to move fast to quell any revolting groups. The Roman roads were cobbled with a base system that was dependent on the subgrade. They developed a three or four layer system, illustrated in Figure 2, consisting of:

Top layer Base, sometimes stabilized Subbase Subgrade

Figure 2.2. Typical

Roman Pavement




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Figure 2. Pavement Structure

Napoleon was responsible for the construction of a considerable network of roads in Europe in the late 18th and early 19th centuries. In 1747, the Ecole des Ponts et Chaussess was founded in Paris, France. In 1765, Tresaguet developed the Roman road structure further. His basic principle was to construct the first layer with big blocks and then to place little rocks in between. By doing this, he attempted to ensure that the first layer was consistently subjected to compressive stresses and improved load spreading on the subgrade was achieved. At the same time, in about 1810 in England, people such as Telford and Metcalf made valuable developments, including:

Design of drainage Design of the road camber Active and regular maintenance Telford and Metcalf found that through drainage design and the inclusion of a crossfall, maintenance could be substantially reduced and the required layer thickness dramatically reduced.

In Great Britain, the Industrial Revolution required a road building programme for the movement of materials and goods, and many kilometres of road were built by various means. During this time, Macadam (1756 to 1836) invented a method of road building as follows: after careful preparation and draining of the roadbed (or subgrade), he laid a 25 cm layer of stone (aggregate size that could fit in a mans mouth), followed by a surfacing of smaller stones. This type of roadway was ideal for animal drawn wagons and coaches, and was cheap to build. John Macadams roads lasted well under traffic and many British roads were macadamised. They were a good solution in the nineteenth century for iron rimmed wheels, i.e., treads. However, the invention of motorised transport by Marcus, who invented the first car with traction in Vienna in about 1870, and rubber tyres developed by Dunlop in 1888, changed the requirements once again. Speeds increased, making safety an important consideration. Rubber-tyred wheels sucked the dust from the road surface, loosening the stones and causing blinding clouds of dust. Hence, in the early part of the 20th century, tar was spread over the road surface to hold the stones in place and to prevent dust. Sand, stone and tar formed a surface dressing. Later the tar-macadam surface of stone coated with tar and rolled to a smooth surface was used, hence the term tarmac. Today we still make waterbound macadam, washing sand into the interstices between the larger stones and penetration macadam by vibrating bitumen-emulsion slurry into the interstices. In South Africa, the pioneer road-builder was Thomas Bain (1830 1893), son of Andrew Geddes Bain. Thomas Bain constructed 23 major mountain passes, nearly all in the Cape Province. Some of his roads are still in use today, e.g., Bains Kloof Pass, shown in Figure 3. The book Romance of the Cape Mountain Passes by Dr G. Ross provides interesting facts about this era of road construction. Some other important developments in the nineteenth century included the train and as a result of technical breakthroughs, the steamroller (a roller powered by steam). Much attention went on the development of the train and in many countries, with a focus on building new railway lines, the roads deteriorated. In 1863, Lemoine invented the two-wheel steamroller, and at the same time Clark and Butler developed the three-wheeled steamroller. This made compaction of granular layers significantly easier and the quality of compaction increased. The impact of changes in technology on the development of roads is conceptualised in Figure 4.




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Figure 3. Bains Kloof Pass

Figure 4. Conceptual Impact of Technological Developments on Roads

2.2 History of Pavement Design

Prior to the early 1920s, the thickness of pavement layers was based purely on experience. The invention of the car and the introduction by Henry Ford of his Model T-Ford in 1908 gave a strong impetus to look at the design of roads more seriously. Twenty million Model T Fords were sold between 1908 and 1927. The traction of a car, i.e., the

Time 2000 BC

500 BC

500 AD

1800 AD

2000 AD

Vehicle

technology

Mesopotamian Persian

Modern

The Wheel

Maximum

aggregate size Traffic

Equipment

Motorisation

Advances in

technology

Roman Middle Ages




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friction between tyre and road, and the vehicle dynamics, damage the surface of the road. Unpaved roads could not cater for this. This resulted in use of the following in the 20th century:

Empirical design systems: experience- and observation-based designs Mechanistic design systems: linking performance to critical pavement properties and failure mechanisms Mechanistic-empirical design systems: linking critical pavement properties to experience based limits In Scotland and Ohio, expensive solutions were found through experimentation. At the same time, experiments were undertaken to investigate tar or natural asphalt, found in a lake in Trinidad, and split (aggregate). Skid resistance and a lack of bond to existing layers, proved problematic. Typical problems of the time, which included impassibility of many unsurfaced roads in wet conditions, can be seen in Figure 5, taken from Floor (1985).

Figure 5. Impassable Unsurfaced Roads Due to Wet Conditions, Early 20th Century

In the period between the First and Second World Wars, the growing importance of roads drove necessary improvements in pavement design. After the Second World War, the growth in traffic, loads and tyre pressures, and the higher speeds, necessitated the development of pavement technology beyond empiricism or designs based on experience only. Functional performance had to be defined, being the basis of the service that is provided to the road users in relation to the cost. This is indicative of fitness for use. Performance also needed to be better understood and more predictable. This required knowledge of structural behaviour and pavement distress in relation to time. This motivated the AASHO road test.

2.2.1. AASHO Road Test

The AASHO Road Test took place in Ottawa, Illinois about 100 km south-west of Chicago between 1956 and 1958. It was an enormous effort to systematically quantify the complex interaction between road deterioration, traffic and composition of the pavement structure on a closed loop test track with trucks. The test track is illustrated in Figure 6.

AASHO stands for American Association of State Highway Officials and later became AASHTO (Highway and Transportation). The aims of the AASHO road test are still very relevant:

Developing satisfactory pavement design procedures to meet the growing demands of traffic. Aid legislators in setting user taxation and control of vehicle size and weight.




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Figure 6. AASHO Road Test

The cost of the AASHO road test was $29 million in 1954 (equivalent to about $300 million in 1996). As a result of the experiment, for the first time the relationship between performance and loading was investigated. The main findings were:

Definition of serviceability as the degree to which the road pavement serves the road users. Development of the Present Serviceability Rating (PSR), where road users rated the serviceability of various

roads.

Present Serviceability Index (PSI) was developed when it was shown that the PSR was more closely correlated with riding quality than with any other variable. Hence, it became possible to estimate the PSR from more objective measurements of roughness, rather than from subjective user ratings. PSI values range from 1 (very good) to 5 (poor).

The concept of load equivalency was defined where the equivalent damage caused by different axle loads and configurations was quantified relative to the 80 kN single axle that was the norm at the time. The AASHO road test showed that different equivalencies also existed for different pavement types (asphalt and concrete).

The load equivalency factor is normally simplified using Equation (1):

(

)

(1)

where LEF P 80 n

= = = =

Load equivalency factor, the relative damage caused by axle load P compared to a 80 kN single axle load Axle load (kN) Equivalent Standard Axle Load (ESAL or E80 in SA) in (kN) damage exponent

The damage exponent depends on the pavement and distress type, but typically 4.2 is used for flexible pavements in

South Africa. See Chapter 10: 4.1.3. A design method was developed from the results of the AASHO Road Test, known as the AASHTO Structural Number method (AASHTO, 1986). This method is discussed in Chapter 10: 7.4.

2.3 Necessity of Roads

In the modern world it is well known that apart from social factors such as transport to hospitals, quick access to a fire and emergencies, visiting friends and tourism, a good road system is the backbone for all kinds of economic activity. It is generally acknowledged that global competitiveness necessitates good road infrastructure. Rural road construction is enormously important and plays a major role in stimulating the economy (farm to market routes).

E80s & MESA

An E80 is an equivalent 80 kN axle load. Typically, varying

axle loads are converted to E80s using Equation 1. Another popular term is MESA, which is Million Equivalent Standard Axles.




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This has been observed in many African countries, where agricultural and mining output increases by an order of magnitude through provision of new road infrastructure. Links to ports are especially important. The 21st century has commenced with an emphasis on:

Improvements in material science and introduction of specialist materials that provide enhanced performance e.g., polymer modified bitumen.

An environmental focus that includes sustainable practice; minimal impact on the environment, i.e., minimising the carbon-footprint and recycling with minimal utilisation of non-renewable resources; and, permeable pavements to reduce run-off.

New priorities and frameworks for procurement and road delivery, including the needs of developing areas, such as Public-Private-Partnering (PPP). See Chapter 11 for procurement and contracting.

Increases in traffic volumes have resulted in the need for increased pavement structural capacity. At the same time, design strategy has moved towards perpetual or long-life pavements. These pavements aim to provide structural capacity for 30 to 50 years with only functional maintenance requirements. It is necessary to adopt long-life pavements in areas where the opportunities for maintenance and rehabilitation interventions are

severely restricted for the following reasons: Road user costs, particularly costs relating to traffic delays, are exorbitant. Access to the road pavement is restricted, resulting in construction being carried out at night or over

weekends.

John F Kennedy

Building a road or highway isnt pretty. But it is something that our economy needs to have!



Section 3. Basic Principles of Roads

Page 10

3. BASIC PRINCIPLES OF ROADS

The history of the development of roads shows that a shift in the paradigm of pavement technology occurred in the 20th century. Since then, the needs extend beyond the technical issues into the functional, environmental and political needs, and amplified with the advent and traffic motorization and growth. The Netherlands Roads Authority, Rijkswaterstaat, captured this trend in a pamphlet (Rijkswaterstaat, 1991) by providing an overview of the different abstraction levels for roads, using two pyramids, as shown in Figure 7.

Figure 7. Road Concepts Political and Technical Pyramids for Roads

3.1 Political Pyramid

The political pyramid includes issues such as:

The public is the customer of road infrastructure, whose perceptions, opinion and needs place high demands on road authorities. In turn, the road authorities have become more aware of their customers requirements.

Policy related to road infrastructure evolves with changing social, economic and environmental needs, the triple bottom line. Examples include: Incentives for labour enhanced construction, or percentage labour component in contracts, toll roads (user pays principle) and carbon credits.

Traffic considerations need to take cognisance of vehicle types and quantities, traffic safety, congestion, accommodation of traffic, geometric capacity and road user costs. The Road Transport Management Systems and Performance Based Standards for heavy vehicles, provide guidance in the field in South Africa. (Nordengen and Naidoo, 2014; Nordengen and Oberholzer, 2006; Nordengen and Roux,

2013; CSIR, 2014)

Road design considerations need to take account of environmental issues, material availability, climate, social issues and traffic requirements.

Materials, both raw and processed, need to be selected based on performance and environmental priorities.

3.2 Technical Pyramid

The technical pyramid represents the pavement engineers understanding of how to manage the pavements response to loads, its subsequent behaviour and ultimately its performance in terms of how well it serves the road users over time. The technical pyramid translates road user needs and functional requirements into measurable

PUBLIC

ROAD USER

NEEDS

FUNCTIONAL

PERFORMANCE

PAVEMENT

BEHAVIOUR

MATERIAL RESPONSE

TO LOADING

NATURE OF MATERIAL

HIGH

LOW

Ab

stra

ctio

n le

vel

Level 1

Level 2

Level 3

Level 4

Level 5

POLITICAL TECHNICAL

POLICY

TRAFFIC

ROAD DESIGN

MATERIALS

PUBLIC

ROAD USER

NEEDS

FUNCTIONAL

PERFORMANCE

PAVEMENT

BEHAVIOUR

MATERIAL RESPONSE

TO LOADING

NATURE OF MATERIAL

HIGH

LOW

Ab

stra

ctio

n le

vel

Level 1

Level 2

Level 3

Level 4

Level 5

POLITICAL TECHNICAL

POLICY

TRAFFIC

ROAD DESIGN

MATERIALS

Environmental Priorities

These include:

Re-use of waste materials, e.g., rubber, slag

Recycling existing pavement materials

Prohibiting use of materials with carcinogenic emissions or leachate

Use of low energy consumption materials



Section 3. Basic Principles of Roads

Page 11

technical requirements at lower abstraction levels. A better understanding of the technical pyramid is normally achieved when it is viewed from the basic building blocks at the bottom to the user requirements at the top:

Nature of Materials. This involves the nature of individual component materials that are used to make up the pavement layers. The pavement engineer needs to have an in-depth understanding of the nature of all the materials that are incorporated in a layer, i.e., mineral aggregates, binders, moisture, additives and how these materials interact and change over time. The nature of materials is discussed further in Chapter 2: 5 and 6 and Chapter 10: 3.5.3.

Material Response to Loading. The pavement engineer needs to understand how all the various pavement layers respond to loading and the stresses that occur within the layers. To understand these interactions, it is first necessary to have a good understanding of the concepts of stress and strain, i.e., mechanics of materials, and typical pavement material models. These concepts are discussed in Chapter 2: 3 (Mechanics of Materials) and Chapter 2: 4.1 (Material Characteristics and Behaviour).

Pavement Behaviour. Pavement behaviour involves understanding the behaviour of the composite system after repeated loads and how the pavement material properties change over time. Structural behaviour is a measure of the rate of change in key structural characteristics, such as deflection, with time. Structural behaviour depends on material properties such as stiffness, resilient modulus, tensile strength, compressive strength and

shear strength, amongst others, as well as the interaction between different layers. Pavement behaviour is discussed in more detail in Chapter 2: 4.1 in Chapter 10: 3.5.

Functional Performance. The pavement engineer needs to understand how different distress patterns translate into functional problems and affect road users over time, and vice versa. Distress types, and their effect on road users, are discussed in Chapter 2: 5 and Chapter 14: 4, and functional performance in Chapter 2: 6.

Road User Needs. At the top of the technical pyramid are the requirements of the road user, set for the pavement. Safety and comfort are amongst the highest priorities, although the environment, economics and health are also considered.



Section 4. Purpose and Classification of Roads

Page 12

4. PURPOSE AND CLASSIFICATION OF ROADS

Roads are provided to serve stakeholders, including individuals, communities, agriculture, industries and government. They serve this process by providing mobility and accessibility to services, jobs and other economic opportunities and activities. In essence, roads are provided for either:

Mobility to facilitate the quick, safe and economic movement of people, goods and services, or Accessibility to facilitate access for people, goods and services to the higher order mobility road network. South Africa has adopted a road functional classification to identify and differentiate the service levels applied. This is set out in detail in the TRH26 (South African Road Classification and Access Management Manual), and is the system as used in the Road Infrastructure Strategic Framework of SA (RIFSA). The TRH26 manual also includes guidelines on providing access and spacings of intersections to reduce potential conflict from turning movements. Figure 8 shows how the different classes of road should be geared to either mobility or accessibility.

Figure 8. Functional Classification of Roads in South Africa

The function of the higher classes of road is almost entirely mobility with some minor accessibility functions. The function of the lower class 5 roads is almost entirely accessibility, although at times they can play a minor mobility role. The higher classes of road have substantial economic and commercial importance. They require greater reliability, higher speeds and better service levels than access roads and, therefore, their pavements are normally designed with this in mind. This differentiation has been given expression by allocating the higher order road network better terminal conditions than the lower order network in the TMH22 Road Asset Management Manual with the road categories defines in TRH4. The TRH26 (RIFSA) and TRH4 road categories with their typical names are given in Table 1.

Functional Classification

Mo

bilit

y/A

cc

es

s

MOBILITY

ACCESS

Class 1

Principal Arterial

Class 2

Major Arterial

Class 3

Distributor

Class 4

CollectorClass 5

Local Access



Section 4. Purpose and Classification of Roads

Page 13

Table 1. Road Classification Systems

TRH26 Functional

Class (RIFSA)

TRH4 Category

Preferred Route Numbering Convention

Preferred Road Numbering Convention

Rural Urban Rural

1 A N M1 - M9 Road number with "N" prefix

2 A R10 - R99 M10 - M99 Road Number with "P" or "TR" prefix

3 B R100 - R999 M100 - M999 Road Number with "P" or "D" prefix

4 C None None Road Number with "D" prefix

5 D None None Road Number with "L" or "m" prefix



Section 5. Institutional Responsibilities

Page 14

5. INSTITUTIONAL RESPONSIBILITIES

There are several role players involved with pavement engineering, including:

Road owners: Ministers, MECs, Councillors and related bodies and structures, or Company Boards in the case of private sector roads.

Road administrators: Public sector departments and agencies, or private sector divisions. Planners and designers: Typically private sector engineering consultants. Construction: Typically contractors with some public sector maintenance and construction units. Each party needs to play its role properly in order to achieve cost-effective results, which are in turn required to keep transportation costs low and ensure country competitiveness. These traditional roles are:

Owners: Policy and funding Administrators: Administration and programme management Designers: Investigations, designs and contract administration Construction: Tendering, work planning and execution

5.1 Owners

In South Africa, owners are typically constituted at the three levels of Government, i.e., national, provincial and municipal. The political component of the Government needs to understand the issues related to road provision to prioritise funding for roads relative to other needs, such as education and health, and to initiate the desired programmes. Owners need to ensure that the underlying administrative bodies are properly staffed and have the requisite skills to carry out their duties. This oversight role should be carried out at a high level without undue interference and micro-management of the administration, while still maintaining an understanding of the quality of service being provided and how this should be improved and/or sustained. Such high level understanding will typically be provided through regular reporting of progress on programmes and also providing indicators of performance and cost-effectiveness. Such benchmarks of effectiveness are typically established at a national level to provide guidance. In certain cases, owners require financial and technical audits to be carried out on their administrators to assess performance.

5.2 Administrators

Administrators in South Africa also typically constitute officials at the three levels of Government. These administrators ensure that their operations, maintenance and construction programmes are drawn up to meet the owners requirements and that the necessary work is procured and carried out cost-effectively. Just as the owners need to understand high level issues associated with road provision, administrators need to have a more detailed understanding of pavement performance to guide planning, investigations, designs and execution, while complying with all the statutory requirements. This entails both day-to-day administration and guidance of their consultants and contractors, as well as making sure that the necessary guidance documentation, such as this manual, are available for use. Administrators include Road Agencies, e.g., SANRAL, as well as Concessionaires, who manage the functional and structural performance a section of road for a defined period, using of toll income generated from vehicles trafficking the route.

5.3 Designers

Designers are typically private sector consulting engineers. These firms need to ensure that they have the necessary expertise available to carry out the investigations and designs. They also need to be familiar with the owners, administrator requirements and related legislation.

5.4 Construction

Construction is typically carried out by private sector contractors. These firms need to ensure that they have the necessary skills to tender for work and also have the resources available to plan and carry out the work. Such resources involve; management, labour, plant, materials and finance.



Section 6. Statutory Requirements

Page 15

6. STATUTORY REQUIREMENTS

All planning, investigations, designs and construction must be carried out in compliance with statutory requirements. As technocrats, pavement engineers prefer to focus on the technical issues pertinent to the design process. The legal issues pertaining to pavement engineering are, however, extremely important and cannot afford to be ignored. These include the following three major areas of legislation:

Environmental legislation Mineral exploitation, including all materials from borrow pits and quarries Health and safety legislation

These areas of legislation, and the specific requirements, are highlighted in broad terms below to create awareness. All parties should be aware of the specific legislation and regulations that need to be complied with during the course of their work. The legal, environmental and other requirements provided in this manual are an indication of those appropriate to the road authorities. The user/practitioner should ascertain the clients specific requirements and be conversant with the necessary legal requirements and procedures prior to embarking on these activities. SAPEM is not intended to be a complete definitive guide to the legal framework and regulations that must be considered in pavement engineering. It must also be recognized that such regulatory requirements are subject to continual review and update. Consequently, this section, along with other related sections, will form

part of a living document which will be updated periodically as required. Specific requirements and principles, as advocated by the relevant environmental regulatory authorities, will be highlighted.

6.1 Environmental Requirements

The protection of the environment is enshrined in the Bill of Rights, which dictates that everyone has a right to a healthy and well protected environment. In the case of roads, typical environmental issues are:

Social environmental impacts caused by both the presence of the road such as noise and traffic adjacent to living areas, schools and hospitals, and the effects of construction of the road, for example, migrant workers.

Physical environmental issues related to the destruction of natural habitat and environmentally sensitive areas by the presence of the road, as well as damage to the environment during construction, such as through diesel spillage, materials excavations, drainage structures and river crossings.

Management of the environment is legislated in South Africa through the National Environmental Management Act 107 of 1998, as amended by:

National Environmental Management Act 56 of 2002

Mineral and Petroleum Resources Development Act 28 of 2002

National Environmental Management Amendment Act 46 of 2003

National Environmental Management Amendment Act 8 of 2004

Any other amendments that may be promulgated from time to time

The regulations published by the Department of Environmental Affairs and Tourism in Government Gazette No. R. 385 21 April 2006, set out who may carry out Environmental Impact Assessments and apply for authorisation of activities, and who can review reports and authorise such activities. Important issues to note are:

The Environmental Assessment Practitioner (EAP) carries out a basic or environmental assessment in relation to any potential activities. The EAP must be independent and have no business, financial, personal or

Legal, Environmental and Other Requirements The legal, environmental and other requirements provided in this manual are an indication of those appropriate to the road authorities. The user/practitioner should ascertain the clients specific requirements and be conversant with the necessary legal requirements and procedures prior to embarking on these activities.

Environmental and Mineral Requirements

Environmental and mineral requirements are also covered in:

Chapter 6: Road Prism and Pavement Investigation

Chapter 8: Material Sources




Page 16

other interest in the works or related activities. There must be no circumstances that may compromise the objectivity of that EAP.

An Environmental Impact Assessment (EIA) Report must be prepared by a competent practitioner and submitted to the Competent Authority to assess. The Authority has 60 days to assess it, or refer it for expert assessment.

Road design and construction is listed as an activity requiring a scoping report to be submitted to the Competent Authority prior to carrying out the comprehensive EIA. It is subject to carrying out the necessary public participation processes, in which potentially interested and affected parties are given an opportunity to comment, or raise issues relevant to the application to carry out the activity. Such interested and affected parties should be registered in terms of the regulations.

Road rehabilitation does not necessarily need an EIA, provided the work is confined to the existing width of the road.

In all cases, the EIA should follow the guidelines laid down by the relevant Competent Authority, usually the Provincial Department of Environmental Affairs. The application for authorisation will be made to the same Department.

The EIA and related authorisation processes can be long and complex, and also include procedures for interested and affected parties to appeal against any authorisation.

It is up to the pavement engineer to ensure that road design and construction activities minimize any environmental impacts, and that the benefits to society outweigh the potential environmental damage. Note should be taken of the time required to carry out the scoping and EIA exercise, including public participation, and finally, authorisation by the Provincial Departments. Environmental issues with sourcing materials are discussed in Chapter 8: 2.

6.2 Mineral Exploitation

6.2.1. Definitions

The Minerals and Petroleum Resources Development Act, 2002 (MPRDA) does not refer to the terminology borrow pits and/or quarries. The Act refers to a mineral (including gravel, rock and stone) and a mining area. In this manual, the terminology borrow pit and quarry are used, but are understood to be a mining area in terms of the act. A list of relevant definitions is included in Chapter 8: 1.

6.2.2. Background

A consistent and high standard of environmental performance is required of contractors and consultants by road authorities in South Africa. Materials investigations and exploration activities associated with road construction activities have the potential to impact adversely on the environment, if not managed appropriately. As such, this section provides an introduction to environmental legal and statutory requirements for these activities. More details are provided in subsequent chapters, particularly Chapters 6 and 8. Prior to any exploration, it is essential for any third party that conducts work on behalf of a roads authority to familiarize themselves with the legislation that relates to their proposed activities. Mineral exploration and mining in South Africa are administered in terms of the Mineral and Petroleum Resources Development Act (MPRDA) (Act No 28 of 2002) (as amended). Note that National Department of Environment Affairs is in the process of amending the 2006 EIA Regulations. It is anticipated that the environmental studies associated with mining areas (borrow pits and quarries) will be included in the new regulations. Through the administration of this MPRDA act, in association with the National Environmental Management Act, applicants for mining permits and/rights can acquire authorizations for access to mineral resources. Other associated legislation impacting on mining activity and as such, on materials investigation and acquisition, are discussed below, as appropriate. For responsible codes of conduct that apply the principles of sound environmental management and industry best practice, please refer to Chapter 6: 3 and Chapter 8.

6.2.3. Regulatory Overview

The regulatory requirements for the various stages of mining are discussed in more detail in Chapters 6 and 8, which fully explain the investigation and management of mining areas. However, the key elements of the Mineral and Petroleum Resources Development Act (MPRDA) that are applicable to road authorities are shown in Table 2.




Page 17

Table 2. Key Environmental Requirements for the Mineral and Petroleum Resources Development Act

Key Requirement MPRDA Reference

Procedure for Roads Authorities in terms of the MPRDA

1. Application for prospecting right Section 16 Exempted from application process

2. Permission to remove and dispose of minerals Section 20 Exempted from application process

3. Application for mining right Section 22 Exempted from application process

4. Application for mining permit Section 27 Exempted from application process

5. Environmental requirements

5.1 Consultation with interested and affected parties Section 10 Not exempted

5.2 Environmental Management Programme and/or Plan

Section 39 Not exempted

5.3 Consultation with state departments Section 40 Not exempted

5.4 Financial provision for remediation of environmental damage1

Section 41 Not exempted

5.5 Issuing of Closure certificate Section 43 Not exempted

Note 1. SANRAL has secured a Memorandum of Understanding (MOU) with DME that stipulates the requirements with regard to

provision for remediation of environmental damage.

Note in Table 2 that the road authorities are generally exempted from the application processes for prospecting and mining related to borrow pits, but have to comply with all the environmental requirements. Therefore, no application needs to be submitted to the DME for prospecting, reconnaissance, mining permit or mining right. However, road authorities are not exempted from conducting and submission of the necessary environmental reports for mining areas to be opened. These include:

An Environmental Management Plan (EMP) needs to be submitted for mining areas less than 1.5 hectares in extent. The EMP needs to be completed by a suitably qualified Environmental Assessment Practitioner (EAP) for submission to the relevant regional office of the Department of Minerals and Energy.

An Environmental Management Programme (EMProg) needs to be submitted for mining areas that exceed 1.5 hectares in extent. The EMProg needs to be prepared following an Environmental Impact Assessment (EIA) process for mining areas exceeding the prescribed limit. The EMProg needs to be completed by a suitably qualified Environmental Assessment Practitioner for submission to the relevant regional office of the Department of Minerals and Energy.

In addition to the requirements of the MPRDA, other South African legislation impacting on exploring and mining activity associated with materials investigation and acquisition include (inter alia):

Mine Health and Safety Act National Water Act National Environmental Management Act (NEMA) EIA Regulations (2006) (as amended) Explosives Act National Forestry Act National Heritage Resources Act

6.3 Health and Safety Legislation

The health and safety of all people involved in the road construction process cannot be compromised. Issues of primary concern are:

Safety in respect of traffic during construction. Safety in deep excavations and cuttings and during the construction of all structures. Safety in respect of harmful materials such as hot bitumen, unhealthy vapours and contact with cement, lime

and cement dust.

Health of all in respect of good sanitation, food and drinking water. Protection from the sun. The proper management of health and safety is legislated through the Occupational Health and Safety Act 85 of 1993 and its regulations. There are many regulations, of which the Construction Regulations are of primary concern during road construction.




Page 18

The pavement engineer should note that this Act and Regulations places responsibilities on various parties, including:

The owner to ensure that the designers, agents and contractors all ensure compliance with the Act. The designer to highlight any particular Occupational Health and Safety (OHS) issues that could arise due to the

design.

The contractor must have an approved OHS plan and ensure that this plan is always adhered to during construction through regular audits. This must include: Carrying out risk assessments to be incorporated into the OHS plan. All personnel and visitors to site must receive OHS induction training and be issued with suitable safety

equipment. All potentially hazardous areas and procedures are identified, and the necessary steps are taken to mitigate

these hazards.

All suppliers to ensure their equipment and materials are handled safely and that the necessary guidelines are available to users.

All employers to ensure that their employees are not unduly subjected to risks in respect of OHS and their procedures, processes and workplaces are safe and healthy. This typically involves the appointment of Health and Safety committees, and ensuring that emergency procedures are readily available and medical help is available for incidents and emergencies.

Compliance with the Act has to be ensured through the development of appropriate procedures and monitoring by competent professionals. In the case of roadworks, many guidelines in this regard are available from industry bodies such as SAFCEC, Sabita and C & CI.



Section 7. Road Design Life Cycle

Page 19

7. ROAD DESIGN LIFE CYCLE

Road design follows several phases. The activities in each phase follow a typical design, construction, operation and maintenance life cycle as set out in Table 3. Generally each phase needs to be completed before moving onto the next phase. The pavement engineering cycle of technology is defined by a loop, illustrated in Figure 9, comprising:

Awareness of the pavement distress mechanisms, followed by Acquiring knowledge of the performance of the pavement materials and key performance properties, leading

to

Developing design tools for the entire pavement system in the climatic and traffic environment, including response to loading and material damage models, culminating in

Implementation of the pavement construction. Closing the loop requires evaluation of the actual pavement performance and recalibration the design models, which

were originally based on laboratory and APT testing.

Figure 9. Pavement Engineering Cycle of Technology

Acquire Knowledge

Develop Tools

Implement

Awareness

Realitycheck and Recalibrate




Page 20

Table 3. Phases of Road Design

Purpose of Investigation Techniques Content

Phase: Planning

Project Stage: Greenfields: Project Statement Geotechnical/Soils/Route/Investigation: Published Geological and Soil Maps

Options identification

Possible impediments: environmental, natural ground risks, property, topography, etc.

Interfaces with existing infrastructure

Likely usage and impacts on existing infrastructure

Identification of significant cost elements

Desk study, including literature review (e.g., case studies)

Asset management documents

Specialist studies, including: wetland studies, Geographical Information Systems (GIS)

Public participation

Social-economic studies

Preliminary economic assessment

Potential environmental risks

Possible options

Likely Costs

Limitations

Social benefits

Project Stage: Upgrading of Existing: Problem Identification

Geotechnical/Soils/Route/Investigation Road asset database, published maps and as-built data

Options identification and prioritisation Pavement surveillance data

Traffic data

Road Asset Management Systems (RAMS) needs assessment and decision support systems

Options

Priorities

Budget/options assessments

Phase: Pre-Feasibility

Project Stage: Initial Assessments Geotechnical/Soils/Route/Investigation: Reconnaissance Surveys

Basic assessment report (BAR) including route location for greenfields

Environmental scoping

Refinement of alternatives

Interpretation of information collected

Recommendations for additional investigations

Determination of general geological conditions

Preliminary indications of foundation conditions

Preliminary indication of construction material resources

Additional public participation, if required

Data collection

Field investigation (walk over investigation)

Regional mapping (geological, land use, agricultural, topographical)

Identification of potential quarry and borrow pit locations and commercial sources

Road and pavement visual assessments

Surveillance measurements

Geophysical investigations

Traffic predictions

Benefit/cost analysis

Initial Assessment Report

Layout plan

Regional engineering geological map

Physiography (topography, climate and geology)

Record of available information

Description of geological conditions

Economic analysis

Recommendations for additional investigation




Page 21


Phase: Feasibility

Project Stage: Preliminary Design Geotechnical/Soils/Route/Investigation: Geotechnical & Materials Report

Final option selection

Determination of general engineering geological conditions

Preliminary design of road (horizontal and vertical alignment) and structures

Interfacing with environmental impact assessment

Interpretation of information collected, needs assessment for the detailed site investigation

Cost assessment

Confident alternative design options

Final scope definition

Environmental and mining approvals

Property expropriation diagrams

Initial drilling and borehole tests for quarries and bridges

Field sampling and surveillance tests

Laboratory testing

In situ testing to obtain quantitative information on the extent of geotechnical problems

Soil and rock mapping

Engineering geological map and profiles of sites (route and material resources)

Detailed materials report (Detailed Assessment and Design Report)

Deterioration modelling and effects of maintenance

Life cycle analysis

Preliminary Pricing Schedule

Provisional costing

Final economic evaluation

Recommendations for specialised testing

Phase: Detailed Design and Documentation

Project Stage: Final Design Geotechnical/Soils/Route/Investigation: Final Investigations. Convert investigation results into designs, specifications and quantities

Final design, drawings and tender documentation documentation

Obtain quantitative and qualitative information on route alignment, foundation conditions, subsurface drainage and construction materials

Description of final design

Specifications

Pricing Schedule

Core drilling for foundations

Input from initial assessment report

Site and resource mapping

Extensive material testing (test pitting, auger samples, material sampling, penetration tests)

Laboratory testing and classification

Pavement design

Detailed drawings

Detail engineering geological maps and profiles

Quantitative and qualitative description on foundations and roadbed /subsurface, design and drawings

Pricing Schedule

Specifications

Final cost estimate

Material Investigation and Utilisation Report Phase: Construction

Project Stage: Construction Geotechnical/Soils/Route/Investigation: Geotechnical Foundation & Bridge Report, Geotechnical Report

Comparison of predicted with encountered conditions/cut and slopes

Observation of behaviour of permanently anchored bridge foundations and founding conditions

Recording all design changes

Detailed mapping/photography and final design

Record of design changes and slope stability measures

Monitoring of bridge foundations and major culverts

Detailed maps

Photos

Design changes

Quality assessment records

As-builts drawings

Materials test results

Construction Report




Page 22


Phase: Operations and Maintenance (Monitoring)

Project Stage: Assessment Report Geotechnical/Soils/Route/Investigation: Special Maintenance & Integrity Reports

Maintenance of road infrastructure and furniture integrity and cost determination

Route inspections

Maintenance of drainage

Integrity of road pavement structures

Subsurface monitoring

Maintenance and monitoring reports

Project management report

Budget for holding and remedial actions, and maintenance

Project Stage: Short Term Monitoring Geotechnical/Soils/Route/Investigation: Integrity Reporting (Structures and Slope Stability Measures)

Comparison of actual and predicted conditions

Attending to ad hoc problems

Observation of behaviour or permanently anchored bridge foundations, lateral support systems and permanently anchored or bolted cuttings and fills, during the Defects Notification Period

Detailed site records

Photos

Monitoring foundation or slope treatments and behaviour via instrumentation and surveillance

Detailed mapping

Photos

Records, measurements and results

Further long term actions or recommendations

Project Stage: Long Term Monitoring (~ 8-10 years) Geotechnical/Soils/Route/Investigation: Integrity Reporting (Structures and Slope Stability Measures)

Same as above for short term monitoring, but at regular intervals during the expected eventual design life of the particular facility

Monitoring of permanently installed devices and/or instruments (mechanically and/or electronically, e.g. deflections, stresses, pressures and water flow) and ongoing verification of integrity.

Records, measurements and results

Evaluation and discussions

Conclusions

Recommendations for either immediate or longer term actions



Section 8. Planning and Time Scheduling

Page 23

8. PLANNING AND TIME SCHEDULING

Significant documentation has been published on planning and time scheduling. The aim of this section is to highlight aspects that need to be considered in the planning and time scheduling of a project. The management of any project always has a 3-dimensional goal:

Delivering the correct project, as agreed upon Not exceeding an approved budget Delivering on time, as specified To achieve the above, planning needs to be carried out in phases, with the end in mind. It is normally difficult to plan activities a few years, or even a few months ahead, in too much detail. Therefore, it is normally more convenient to break a project into phases:

Preliminary Investigation and/or Route Location Preliminary Design Detailed Design and Documentation Tender and Construction Defects Notification These phases can be broken up further into smaller activities, with milestones linked to each activity. The time required for carrying out these technical activities can be determined and scheduled. There are a number of useful software packages on the market to aid project management.

8.1 Non-Technical Factors

There are a number of non-technical activities and issues that need to be resolved before a project can proceed. Each project has elements of uniqueness, which need to be identified at the start of the planning process, and considered in the project management programme. The following non-technical issues and activities will typically delay delivery of the programme if not properly managed:

Land requirements: Allow enough time to acquire land including: Road reserve Access roads Borrow pits and quarries Stockpile areas Temporary deviations

Climate restrictions: Embargo periods for certain activities and areas.

Survey and testing: Topographical surveys and mapping, traffic surveys and geotechnical and materials investigations and testing.

Budget: The project can only start when the cash flow is available. Environmental approval: No control over time taken to get

approval.

Approval for mineral exploitation of borrow pits and quarries.

8.1.1. Land Acquisition

The land acquisition procedures for the different Road Authorities vary. SANRALs procedures are dealt with in detail in the relevant chapters of this manual. It is necessary to be aware of the types of land normally encountered in any design. The land type holds the unique factors that influence the ultimate timeframes and construction of a designed road, and dictate the parameters within which a design is confined. There is a need to differentiate between the types of land, as shown in Table 4.

Land Acquisition

The land acquiring process can run parallel with the Preliminary and Detailed Design, but must be resolved before the site is handed over to the Contractor.

Project Management

The expression on time, on budget, on brief is often used to describe the basic project management requirements.

Time Required for Environmental Approvals

The time required for environmental approvals and approvals for mineral exploitation can be extensive, and must be considered at all stages of a project. Chapter 8: 2.5 contains more information on these processes.



Section 8. Planning and Time Scheduling

Page 24

8.1.2. Climate Restrictions

Due to low day and night temperatures at certain times of the year, an embargo is enacted for when road surfacing is not allowed. The embargo period is normally between May and September. Road surfacing actions therefore need to be programmed to take place between September and April. This means that the time for completion should be by mid-April to allow for a possible contract time extension. Other activities can still proceed during t

SAPEM Chapter 1 2nd Edition 2014

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